U.S. patent number 7,824,249 [Application Number 11/702,217] was granted by the patent office on 2010-11-02 for polishing material having polishing particles and method for making the same.
This patent grant is currently assigned to San Fang Chemical Industry Co., Ltd.. Invention is credited to Chung-Chih Feng, Yung-Chang Hung, Chao-Yuan Tsai, Lyang-Gung Wang, I-Peng Yao.
United States Patent |
7,824,249 |
Feng , et al. |
November 2, 2010 |
Polishing material having polishing particles and method for making
the same
Abstract
The present invention relates to a polishing material having
polishing particles and a method for making the same. The polishing
material having polishing particles includes a base material, a
plurality of polishing particles and a polymer elastic body. The
base material has a plurality of fibers for defining a plurality of
grid-spaces. The polishing particles are distributed in the
grid-spaces. The polymer elastic body covers the base material and
the polishing particles, whereby, the polishing particles are
uniformly distributed on a surface of a polishing workpiece during
the polishing process. Furthermore, the base material prevents the
polishing particles from contacting the polishing workpiece so as
to avoid scratching of the polishing workpiece. Also, the base
material provides effects for sweeping the small grinded
pieces.
Inventors: |
Feng; Chung-Chih (Kaohsiung,
TW), Yao; I-Peng (Kaohsiung, TW), Wang;
Lyang-Gung (Kaohsiung, TW), Hung; Yung-Chang
(Kaohsiung, TW), Tsai; Chao-Yuan (Kaohsiung,
TW) |
Assignee: |
San Fang Chemical Industry Co.,
Ltd. (TW)
|
Family
ID: |
39676581 |
Appl.
No.: |
11/702,217 |
Filed: |
February 5, 2007 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20080188168 A1 |
Aug 7, 2008 |
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Current U.S.
Class: |
451/532; 51/295;
451/527 |
Current CPC
Class: |
B24B
37/26 (20130101); B24D 11/001 (20130101) |
Current International
Class: |
B24D
15/00 (20060101); B24D 11/00 (20060101); B24B
1/00 (20060101) |
Field of
Search: |
;451/527,532 ;51/295
;427/430.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1438930 |
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Aug 2003 |
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CN |
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1843701 |
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Oct 2006 |
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CN |
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59118374 |
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Jul 1984 |
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JP |
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490364 |
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Jun 2002 |
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TW |
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Other References
Peoples Republic of China Office Action dated Jul. 31, 2009,
corresponding to the Peoples Republic of China Patent Application
No. 2007100800115. cited by other.
|
Primary Examiner: Green; Anthony J
Assistant Examiner: Parvini; Pegah
Attorney, Agent or Firm: Sughrue Mion, PLLC
Claims
What is claimed is:
1. A method for making a polishing material having polishing
particles, comprising: (a) providing a base material having a
plurality of fibers for defining a plurality of grid-spaces; (b)
immersing the base material in a polymer solution containing a
plurality of polishing particles, such that the polishing particles
are distributed in the grid-spaces; (c) solidifying the polymer
solution attached to the base material to form a polymer elastic
body for covering the base material and the polishing particles, to
form a polishing material, wherein the polishing material has a
first surface and a second surface corresponding to the first
surface; (d) polishing the first surface; and (e) trimming the
second surface so as to expose the fibers on the second
surface.
2. The method according to claim 1, wherein step (c) further
comprises a step of coagulating the polymer solution attached to
the base material.
3. The method according to claim 2, further comprising a washing
step, after the step of coagulating the polymer solution attached
to the base material.
4. The method according to claim 3, further comprising a baking
step to solidifying the polymer solution, after the washing
step.
5. The method according to claim 1, wherein the method further
comprises a step of forming a plurality of grooves on the second
surface after step (e).
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a polishing material and a method
for making the same, and more particularly to a polishing material
having polishing particles and a method for making the same.
2. Description of the Related Art
Generally, polishing refers to grinding a rough surface through a
chemical mechanical polishing (CMP) process. Particularly, a
polishing slurry having polishing particles is uniformly
distributed on a surface of a polishing pad, and meanwhile, a
workpiece to be polished bears against the polishing pad, then, a
repeated and regular rubbing operations are performed. The
workpiece to be polished includes, for example, a semiconductor, a
storage medium substrate, an integrated circuit, an LCD flat glass,
an optical glass, or a photoelectric panel, etc.
FIG. 1 is a schematic view of a conventional polishing pad. The
conventional polishing pad 1 does not have polishing particles, and
has a plurality of grooves 11 on a surface of the polishing pad 1.
When performing a polishing process on a workpiece to be polished
(not shown), a polishing slurry containing polishing particles is
applied between the workpiece to be polished and the polishing pad
1, and thus, the polishing particles in the polishing slurry are
used for polishing. However, the distribution of the polishing
slurry between the workpiece to be polished and the polishing pad 1
is restricted by the design of the grooves 11, so that the
polishing particles cannot be uniformly distributed, and thus the
polishing efficiency is reduced and the used polishing slurry
easily causes pollution.
FIG. 2 is a schematic view of a conventional polishing pad
disclosed in U.S. Pat. No. 5,692,950. The polishing pad 2 comprises
a base 21, an adhesion layer 22, and a polishing layer 23. The base
21 comprises an elastic layer 211 and a stiff layer 212. The
adhesion layer 22 is disposed on the stiff layer 212. The polishing
layer 23 comprises a backing layer 231 and a polishing structure
232, wherein the backing layer 231 is disposed on the adhesion
layer 22. The polishing structure 232 has a predetermined pattern
and a plurality of fixed polishing particles 233. The polishing
particles 233 are distributed within the polishing structure 232
and on the surface of the polishing structure 232.
Similarly, when polishing a workpiece to be polished (not shown), a
polishing slurry containing polishing particles is applied between
the workpiece to be polished and the polishing pad 2, so as to
enhance the polishing effect. Although the polishing pad 2 has the
polishing particles 233, the main body of the polishing structure
232 is a PU material with independent foam, and the polishing
particles 233 exist in the individual holes of the polishing
structure 232, and thus the polishing particles 233 have no
fluidity. During the polishing process, the polishing particles 233
on the surface of the polishing structure 232 directly contact the
surface of the workpiece to be polished, or after the polishing
structure 232 has been polished for a period of time, the polishing
particles 233 within the polishing structure 232 are exposed and
directly contact the surface of the workpiece to be polished, thus
causing the surface of the polished workpiece to be scratched.
Consequently, there is an existing need for providing a polishing
material having polishing particles and a method for making the
same to solve the above-mentioned problems.
SUMMARY OF THE INVENTION
One objective of the present invention is to provide a polishing
material having polishing particles. The polishing material having
polishing particles comprises a base material, a plurality of
polishing particles, and a polymer elastic body. The base material
has a plurality of fibers for defining a plurality of grid-spaces.
The polishing particles are distributed in the grid-spaces. The
polymer elastic body covers the base material and the polishing
particles
Another objective of the present invention is to provide a method
for making a polishing material having polishing particles, which
comprises: (a) providing a base material having a plurality of
fibers for defining a plurality of grid-spaces; (b) immersing the
base material in a polymer solution containing a plurality of
polishing particles, such that the polishing particles are
distributed in the grid-spaces; and (c) solidifying the polymer
solution attached to the base material to form a polymer elastic
body that covers the base material and the polishing particles.
By using the polishing material having polishing particles and the
method for making the same of the present invention, the polishing
particles are uniformly distributed on the surface of the workpiece
for being polished during the polishing process. Therefore, the
polishing material having polishing particles and the method for
making the same of the present invention is capable of solving the
problem of the reduced polishing effect and the pollution of the
used polishing slurry caused by the conventional polishing material
without containing polishing particles that the polishing particles
in the polishing slurry are not uniformly distributed during the
polishing process.
Moreover, the base material of the present invention prevents the
polishing particles from directly contacting the polished
workpiece, thus solving the problem of the surface of the polished
workpiece to be scratched caused by the conventional polishing
material as an independent foam material that the polishing
particles are existed in the independent holes and have no
fluidity. Moreover, the base material of the present invention also
provides an effect for sweeping the small grinded pieces.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a conventional polishing pad;
FIG. 2 is a schematic view of a conventional polishing pad as
disclosed in U.S. Pat. No. 5,692,950;
FIG. 3 is a schematic view of a base material of the present
invention;
FIG. 4 is a schematic view of immersing the base material in a
polymer solution containing a plurality of polishing particles
according to the present invention;
FIG. 5 is a sectional view of a polishing material having polishing
particles of the present invention;
FIG. 6 is a sectional view of a polishing material having polishing
particles with part of fibers being exposed when the surface is
polished according to the present invention; and
FIG. 7 is a sectional view of a polishing material having polishing
particles with a plurality of grooves formed on the surface
according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a polishing material having
polishing particles. The polishing material is applied in a
chemical mechanical polishing (CMP) process for grinding or
polishing a workpiece to be polished. The workpiece to be polished
includes, but not limited to, a semiconductor, a storage medium
substrate, an integrated circuit, an LCD flat glass, an optical
glass, and a photoelectric panel, etc.
FIGS. 3 to 7 show a method for making the polishing material having
polishing particles according to the present invention. Referring
to FIG. 3, a base material 31 is firstly provided, which has a
plurality of fibers 311 for defining a plurality of grid-spaces
312. Preferably, the thinness of the fibers 311 falls between 0.001
den and 10 den. The base material 31 is a fabric material, and it
is a non-woven fabric in the embodiment. Preferably, the material
of the fibers 311 is selected from a group consisting of
polypropylene (PP), polyester (PET), nylon, or a combination
thereof.
Referring to FIG. 4, the base material 31 is immersed in a polymer
solution 33 containing a plurality of polishing particles 32, such
that the polishing particles 32 are uniformly distributed in the
grid-spaces 312. In the embodiment, the polymer solution 33 is
selected from polypropylene (PP), polyester (PET), or polyurethane
resin. Preferably, the polishing particles 32 are selected from a
group consisting of ceria, silicon dioxide, aluminum oxide, yttria,
ferric oxide, or a combination thereof, and the diameter of the
polishing particles 32 is between 0.01 .mu.m and 10 .mu.m.
Referring to both FIGS. 4 and 5, the polymer solution 33 attached
to the base material 31 is solidified to form a polymer elastic
body 34 for covering the base material 31 and the polishing
particles 32 in the grid-spaces 312, so as to form a polishing
material 3 having polishing particles. The polishing material 3
having polishing particles has a first surface 301 and a second
surface 302 corresponding to the first surface 301. In the
embodiment, a step of coagulating the polymer solution 33 attached
to the base material 31 is performed first, then, a washing step is
performed, and finally, a baking step is performed for
solidification, so as to form the polishing material 3 having
polishing particles.
Referring to FIG. 6, after the solidifying step, the method of the
invention preferably comprises a step of polishing the first
surface 301, such that the first surface 301 has a preferred
evenness. Then, the second surface 302 is trimmed, such that the
polishing material 3 having polishing particles has an appropriate
thickness. In the embodiment, the second surface 302 is used as a
polishing surface for the polishing material 3 having polishing
particles during the polishing process.
After the polishing material 3 having polishing particles is
formed, the first surface 301 is first polished to obtain a
relatively even surface, which ensures that the successively
trimmed second surface 302 has a more preferred evenness, i.e., the
polishing material 3 having polishing particles has a consistent
thickness, and thus, the stress applied on the surface of the
workpiece to be polished by the polishing material 3 having
polishing particles during the polishing process is relatively
uniform, so that a more even polished surface is produced.
Moreover, since the polymer elastic body 34 is a harder material
compared with the fibers 311 of the base material 31, when the
second surface 302 is trimmed, a part of the polymer elastic body
34 of the second surface 302 is removed first, such that part of
the fibers 311 is exposed on the second surface 302 of the
polishing material 3 having polishing particles.
Referring to FIG. 7, after the step of trimming the second surface
302, the method of the invention preferably comprises a step of
forming a plurality of grooves 303 on the second surface 302.
According to various applications, the grooves 303 have a
geometrical shape of triangle, square, or rectangle.
FIG. 7 shows a polishing material having polishing particles of the
present invention. The polishing material 3 having polishing
particles comprises a base material 31, a plurality of polishing
particles 32, and a polymer elastic body 34. The base material 31
has a plurality of fibers 311 for defining a plurality of
grid-spaces 312. Preferably, the thinness of the fibers 311 falls
between 0.001 den and 10 den. The base material 31 is a fabric
material, and it is a non-woven fabric in the embodiment.
Preferably, the material of the fibers 311 is selected from a group
consisting of polypropylene (PP), polyester (PET), nylon, or a
combination thereof.
The polishing material 3 having polishing particles has a first
surface 301 and a second surface 302 corresponding to the first
surface 301, and part of the fibers 311 is exposed on the second
surface 302 of the polishing material 3 having polishing particles.
Therefore, the exposed fibers 311 prevent the polishing particles
32 from directly contacting the polished workpiece (not shown), and
thus solving the conventional problem of the surface of the
polished workpiece to be scratched caused by that the polishing
particles of the polishing material with independent foam are
existed in the independent holes and have no fluidity.
Moreover, according to the present invention, the fibers 311
exposed on the second surface 301 also provides an effect of
sweeping the small grinded pieces, and solves the problem of the
pollution caused by the used polishing slurry. In the embodiment,
the polishing material 3 having polishing particles further
comprises a plurality of grooves 303 formed on the second surface
302, and depending upon various applications, the grooves 303 may
have a geometrical shape of triangle, square, or rectangle. The
grooves 303 are formed to make the particles in the polishing
slurry be more uniformly distributed, and by using the polishing
particles 32 of the polishing material 3 together, a more preferred
polishing effect can be achieved.
The polishing particles 32 are distributed in the grid-spaces 312.
In the embodiment, the polishing particles 32 are selected from a
group consisting of ceria, silicon dioxide, aluminum oxide, yttria,
ferric oxide, or a combination thereof. Preferably, the diameter of
the polishing particles 32 falls between 0.01 .mu.m and 10 .mu.m,
such that the polishing particles 32 are uniformly distributed in
the grid-spaces 312 defined by the fibers 311, and a preferred
polishing efficiency is achieved during the polishing process.
The polymer elastic body 34 covers the base material 31 and the
polishing particles 32, so as to form the polishing material 3
having polishing particles. In the embodiment, the polymer elastic
body 34 is selected from polypropylene (PP), polyester (PET), or
polyurethane resin, and the polymer elastic body 34 is a continuous
foam body.
The polishing particles 32 of the present invention are uniformly
distributed within and on the polishing material 3, thus a
preferred effect of uniformly covering the polished surface is
achieved during the polishing process. Furthermore, the base
material 31 prevents the polishing particles 32 from directly
contacting the polishing workpiece, so as to prevent the polishing
workpiece from being scratched, and also provides an effect of
sweeping the small grinded pieces.
While the embodiments of the present invention have been
illustrated and described, various modifications and improvements
can be made by those skilled in the art. The embodiments of the
present invention are therefore described in an illustrative but
not restrictive sense. It is intended that the present invention
may not be limited to the particular forms as illustrated, and that
all modifications that maintain the spirit and scope of the present
invention are within the scope as defined in the appended
claims.
* * * * *